Networks have enhanced our ability to communicate and access information by allowing one personal computer to communicate over a network (or network connection) with another personal computer and/or other networking devices, using electronic messages. When transferring an electronic message between personal computers or networking devices, the electronic message will often pass through a protocol stack that performs operations on the data within the electronic message (e.g., packetizing, routing, flow control).
The first major version of addressing structure, Internet Protocol Version 4 (IPv4), is still the dominant protocol of the Internet, although the successor, Internet Protocol Version 6 (IPv6) is being deployed actively worldwide. The IPv6 network protocol provides that IPv6 hosts or host devices (for example, image forming apparatuses and other devices) can configure themselves automatically (i.e., stateless address autoconfiguration) when connected to an IPv6 network using ICMPv6 neighbor discovery messages (i.e. Neighbor Discovery Protocol or NOP).
When first connecting to a network, an IPv6 host (or node) sends a link-local multicast neighbor solicitation request advertising its tentative link-local address for double address detection (dad), and if no problem is encountered, the host uses the link-local address. The router solicitations are sent (or router advertisements are received depending on timing) to obtain network-layer configuration parameters, and routers respond to such, a request with a router advertisement packet that contains network-layer configuration parameters.
OAuth2 (or OAuth 2.0) is an authorization framework that enables applications to obtain limited access to user accounts on an HTTP service. OAuth2 delegates user authentication to a service that hosts the user account, and authorizes third-party applications to access the user account. OAuth2 provides authorization flows for web and desktop applications, and mobile devices.